Mccoy m. gibson, jr. c. marshall dann

ABSTRACT

A MEAT REPLACEMENT IS PREPARED EMPOLYING PROTEIN CONTAINING A SUFFICIENT CONCENTRATION OF DENATURABLE AND UNDERNATURED PROTEIN MOLECULES BY DENATURING THE PROTEIN SOURCE RAPIDLY IN LESS THAN 5 MINUTES IN A CONTINUOUS REACTOR WHEREIN SAID SOURCE IS AGITATED WHILE IN HEAT EXCHANGE RELATION AND EXTRUDED AT A TEMPERATURE OF 300 TO 400*F. AND THEN COOLED.

United States Patent Office Re. 27,790 Reissuecl Oct. 16, 1973 Int. Cl.A23j US. C]. 99-14 3 Claims Matter enclosed in heavy brackets appears inthe original patent but forms no part of this reissue specification;matter printed in italics indicates the additions made by reissue.

ABSTRACT OF THE DISCLOSURE A meat replacement is prepared employingprotein containing a sufficient concentration of denaturable andundenatured protein molecules by denaturing the protein source rapidlyin less than 5 minutes in a continuous reactor wherein said source isagitated while in heat exchange relation and extruded at a temperatureof 300 to 400 F. and then cooled.

This invention relates to the production of meat-like food products fromvegetable and animal protein sources. More particularly, the inventionrelates to the production of a meat-like, edible mass of protein havinga texture and appearance simulating that of muscle protein found incommon meat products like steaks, fowl, chops, hams and the like.

Heretofore, food technologists have borrowed liberally from the art ofmaking so-called man-made fibers for the textile industry to produce afood product having a fibrous texture. Such work has been carried out inan efiort to simulate the fibrous eating quality of meat. Such practiceshave followed the procedure of spinning a protcin dope solution intofilaments whereafter the protein filaments are precipitated in an acidbath. The protein fibers are thereupon collected and assembled into towsor otherwise aggregated and eventually compounded to produce meat-likeproducts. Unfortunately, such fibers have the limitation that they arenot capable of being cooked without disintegration. Binders must beemployed in order to aggregate the fibers and such binders do notprovide a sufiiciently permanent cementing or aggregation of the fibers.

It would be desirable to provide a meat-like food prodnot from such highprotein sources as various vegetable protein meals as well as fromlow-cost cuts of meat. In addition, it would be desirable to provide aprocess whereby a more meat-like texture and appearance is offered thanthat which is provided by following the practices of the man-made edibleprotein fiber art as taught heretofore.

It is an object of the present invention to provide a meat-like textureand appearance from inexpensive sources of raw materials. A furtherobject of the invention is to provide a meat-like texture and appearancein a product which has the ability to be cooked by deep fat frying,roasting, boiling or by any other means where elevated temperatures maybe used without causing disintegration and loss of the structure andtexture created. Still another object of the invention is to provide aproduct having the aforegoing characteristics which can be dehydratedwithout loss of texture or appearance upon rehydration and cooking.

It has now been discovered that the foregoing objects of the presentinvention can be accomplished by the rapid orientation and coagulationof protein material in a substantially undenatured, finely-divided,hydrated state under conditions which produce a shred-like structure. Incarrying out the present invention, orientation and coagulation of theprotein must be related one to the other so that coagulation followsorientation of the molecules whereby upon the action of the coagulationinfluence the molecules are set in a shred-like condition.

The protein must be present in a suflicient concentration to permit theprotein molecules to be juxtaposed proximate one another prior tocoagulation. The degree of concentration of the hydrated protein isdependent upon and will be varied in accordance with the source ofprotein being treated. For raw materials such as beef liver, theconcentration can be reduced in comparison with proteins like soy whichcall for a higher concentration in order to arrange more proteinmolecules in suspension in close proximity with one another such thatupon coagulation the molecules will become aggregated.

An animal protein source such as cheap cuts of meat, poultry or fish;meat scraps, poultry scraps or fish scraps; or a vegetable proteinsource such as soy bean meal, peanut, cottonseed or other vegetableprotein meal high in protein recovered as by-products from theexpression or solvent extraction of desired oils from source materialslike soy beans, peanuts, cottonseeds, and the like, is comminuted toform a homogeneous mass which is used to form a paste or slurry by theaddition of an aqueous liquid. Preparation of the paste or slurry iscarried out under conditions wherein further denaturation of the proteinis substantially avoided. Thus, room temperature water may be blendedwith the comminuted mass to obtain the desired consistency. It is afeature of the present invention also that other additives or modifyingagents may be incorporated into the homogeneous mass prior to processingand included in this list of compounds are fats and oils, flavoringmaterials, protein hydrolyzates offering flavoring enhancement, meatextracts, colors and the like. Such additives or modifiers, of course,are in addition to the non-proteinaceous constituents of the proteinsource, which constituents, in the case of vegetable protein sourcesnormally comprise a substantial proportion of carbohydrates. In thisconnection, it is also to be noted that a so-called fat-free vegetableprotein meal or a protein meal which is not reduced to the levelcustomarily encountered in recovering a vegetable protein meal from anoil expelling operation may be employed. Also, the liquid employed toform the slurry may be any aqueous liquid, preferably water butincluding such materials as milk, blood, salt solution and any otheraqueous solution.

The foregoing hydrated paste or slurry is introduced into a reactionvessel, typically an autoclave designed in such a manner that steam maybe injected into the homogeneous mass at the appropriate time. In thedesign of any reaction vessel for carrying out the present process,means must be provided for effectively agitating the protein mass inorder to effect orientation and also to heat the mass rapidly in orderto properly coagulate the protein when the discrete molecules are inproper juxtaposition with respect to one another. In this connection,the rapid orientation and coagulation are distinct features of thepresent invention for unless the material is adequately agitated,sufiicient orientation of the proteinaceous material into a conditionallowing it to be coagulated into a shred-like structure will not occur;instead a mass of coagulated protein not having any shred-like structurewill be formed. Similarly, in the case of rapid heating to elfectcoagulation, the efiect of rapid heating is to coagulate the entire massin a substantially short length of time, say instantaneously; if heatingis carried out in such a manner that it takes place slowly, the mass isdifferentially heated so that a shred-like coagulation does not takeplace. On the other hand, the rates at which agitation and heating arecarried out are within the limits whereby the size of the shred-likeformations may be controlled. In some products where an extremelyelongated shred-like texture would be desired as in the case of chickenbreast, harms and any area where the texture of muscle protein is beingsimulated, an extremely rapid agitation and rapid heat coagulation ispracticed. In cases where short shreds are desired, correspondingly lessrapid agitation and heating is carried out.

In carrying out the process of the present invention in the reactionvessel specified hereinabove, the steam introduced at the lowerextremity of the reaction vessel under a high pressure heats the slurryor paste-like mass thereby reducing its viscosity and facilitatingorientation through the combined agitating effect of the agitator andthe steam. In this connection, it is possible to poise the steamintroduced to the reaction vessel in such a manner as to replace all orpart of the agitation produced by the rapidly spinning blades. Incarrying out agitation to effect proper orientation of the molecules asstated hereinabove it is important to practice the proper concentrationof protein material with respect to the liquid medium as well as theother additives or modifiers employed in compounding the slurry orpaste. At too low a concentration an insufficient number of denaturableor precipitable protein molecules will be present so that they will notjuxtapose themselves relative to one another in a linear form wherebythey will produce a shred-like mass upon coagulation.

As the temperature is elevated, the protein material will be denaturedand will set-up into the coagulated shread-like form desired. Inachieving this denaturation, it is important as indicated above that thedenaturation temperature which is a function of the raw material beingprocessed be arrived at rapidly in less than about five minutes andpreferably instantaneously in order that the entire mass can becoagulated at substantially the same time. Otherwise, the orientedprotein molecules will denature differentially and disallow theformation of shreds. Various heating methods may be used provided theyperwit the desired rapid rate of uniform heating which will preventselective denaturation. Agitation is employed to provide uniformity oftemperature throughout the batch and to provide the requiredorientation. In lieu of the foregoing batch-type of operation acontinuous system may be employed which comprises means of adequatelyorienting a continuous flowing stream of the protein paste and means forapplying heat to hydrate and coagulate the oriented mass. Thus, acontinuous reactor, wherein agitation is provided by suitable mechanicalmeans, or by introducing steam or both, and wherein heat is applied byjacketing with suitable materials such as dowtherm or high pressuresteam, or by introduction of steam to the mass, or both, will provideconditions suitable for shred formation.

In carrying out the present invention, a protein source such as beefmuscle, trimmings or scraps; beef liver, trimmings or scraps; otheredible portions of beef; lamp or pork muscle, trimmings or scraps;poultry muscle, trimmings or scraps; fish muscle, trimmings or scraps;fish flour; or vegetable protein flour and the like, is treated as bycomminution to effect a homogeneous mixture. It is preferred that theprotein content of the protein source be 30-100% of the solids on a drybasis and in the case of vegetable protein, as high as possible forreasons of control. One means of preparing the homogeneous mixture,particularly in the case of meat or meat by-products is by grindingthrough a meat grinder having Vs-l" holes.

The protein source is admixed with sufiicient moisture in the form ofwater or other aqueous liquid to prepare a slurry or paste having a5080% moisture content.

The paste or slurry is placed in a reaction vessel, typically anautoclave or continuous reactor such as the V- tator and heated rapidlyto a temperature of 300400 F. and preferably 330360 F. Where the slurryor paste is heated to less than 300 F., little or no fiber formationtakes place whereas at temperatures above 400 F. the fibers or masses ofshreds start to decompose with a resultant loss of cohesiveness,chewiness and texture. The heating of the paste from room temperature tomaximum temperature should be rapid and generally a heating period ofless than 5 minutes is preferred, 1 to 2 minutes being most preferred.If the rate of heating is so slow that a temperature of about 400 F. isnot reached in about 5 minutes, the resultant product is soft, lacks thedesired cohesiveness and shred character, and contains excessivelydegraded protein.

During heating, agitation should be maintained constantly to provideuniform heat transfer and prevent charring of the product and also toaid in the orientation and stretching of the molecules so that they areplaced in proper juxtaposition with respect to one another prior tocoagulation. Preferably the agitating device employed should rotate inthe order of 30-500 r.p.m. in order to obtain the desired shreds andchunks of shreds. At agitation rates over about 500 rpm, shreds andchunks of shreds tend to break down into smaller units which are not asdesirable.

As soon as the paste or slurry has been heated to the desiredtemperature, cooling is commenced and is carried out as rapidly aspossible until a temperature of at least 200 F. and preferably to F. isreached.

The resulting cooled product will generally be obtained in a yield ofabout 30-85% of the total starting solids in the form of shreds ormasses of shreds, the remainder of the starting material existing as asoupy mass which may contain small fragmentary shred particles, theyield being dependent upon the starting material employed and theprocessing conditions utilized. The soupy mass may be recycled insubsequent batches depending upon the raw material source to providefurther shred formation. Such formation will to a large extent depend onthe degree of protein degradation, the protein concentration, the sourceof original starting material, etc.

The cooled shreds are separated from the supernatant liquid, usually inthe form of a soupy mass by any common means such as screening,decanting, etc. The shreds generally have a solids content 5-l0% higherthan the solids content of the starting material. The shreds may bewashed, sliced, flavored and color added or they may be first bleachedand then subsequently flavored and colore The shreds may be used in foodpreparations which would employ meats such as beef, chicken, fish, andmay be used in a variety of products calling for the use of such proteinshreds or for nutritious non-meat components.

The invention will now be more fully described by the followingexamples:

Example 1 A meat replacement was prepared employing soy flour derived bythe hexane extraction of soy bean oil from soy beans, the soy flourbeing substantially undenatured and having a moisture content in theorder of 10% by weight. About 8 pounds of this soy flour was mixed with10 pounds of water and slurried in a Day Mixer to produce a thick paste.The paste was then introduced to an autoclave having a S-galloncapacity.

The autoclave used was equipped with a jacket piped for steam heatingand water cooling, a thermowell extending into the center of theautoclave cavity to contain a thermocouple (which when attached to apotentiometer was used to determine internal temperature of theautoclave), a valved vent opening for the relief of gases from the headof the autoclave, a pressure indicating gauge, a separate opening pipedto a rupture disc as a safety relief, and a flush valve in the base ofthe autoclave normally acting as a discharge port but adapted to serveas a stream injection port during the process. The interior of theautoclave was also fitted with cooling coils and an anchor typeagitator. The agitator blades were approximately 9% inches across andthe width of the vessel 10 inches, thus providing close clearance forprevention of material adhering and building up on the side walls.Variable agitator speeds weer provided via the use of various sheaves.The coils piped for water cooling, described a cylinder above theagitator blades and proximate to the side walls.

Following introduction of the soy flour paste charge, the autoclave wasclosed and steam was introduced through the steam-injection port to heatthe paste. Initially a period of 5-10 seconds of iniection of 40p.s.i.g. steam was required in order to reduce the viscosity of thepaste sufficiently to start agitation. Thereafter, steam wascontinuously introduced to the autoclave and the agitator was operated a400 r.p.m. Agitation and heating under the above-specified conditionsfor approximately 1 minute and seconds provided a charge temperature of360 F. as read with the potentiometer whereafter steam-injection wasterminated and cooling water was circulated through the cooling coilsand through the jacket surrounding the reaction vessel to cool thecharge down to approximately 100 F. as read with the potentiometer.

Upon opening the autoclave, it was found that through this operation theprotein was coagulated to produce shred-like fibrous material. Shredformations were collected from the cooling coils as well as from thebase of the vessel. Forty percent by weight of the solids fed to thereactor were recovered in the desirable shred form.

In a further extension of this example the thin nonshred containingslurry which remained after collection of the shreds was utilized withfresh soy paste in the preparation of more shred material. A similarpercentage of solids were converted to the shred stage indicating thepotential utility of this residual slurry and higher overallconversions.

The materials as collected had semblances of meat roasts or chickenparts. The composition, in addition to its shred-like gross appearance,had a plastic-pliable somewhat elastic nature which permitted physicalcompaction of the fiber, if desired, to give various elongatedcontinuous structures, meat-like in texture. The material was dehydratedand thereafter rehydrated readily upon water cooking. It was alsopossible using the product of this example to freeze the meat-likestructure and to rethaw it without loss of texture in the manner ofordinary cuts of meat. Upon cooking either after recovery from thereaction vessel, freezing or dehydrating the material very substantiallyretains its original shape and texture. In the mouth, the compositioncould be generally characterized as non-sinewy, yet it held togethercohesively, approaching the eating textural properties of meat.

The product can be conditioned or modified in terms of flavor and aromaas well as in terms of texture by smoking and/or by the incorporation ofmodifying agents. By boiling the shred-like composition in bouillon orsoup stock, it was observed to absorb much of the flavors present;preferably this fortification of the product with flavor is carried outsubsequent to dehydration under which condition the dehydrated productof this invention swells and absorbs greater quantities of flavoringingredients. When fried in butter, a crisp, crunchy product simulatingchitlins or the lean of bacon was noted.

Advantageously in comparison with ordinary dehydrated cuts of beef andother types of meat, the product will rehydrate to a less tough texturewithout an loss in rate of rehydratability. This property allows theproduct to be employed in either a dehydrated or hydrated condition invarious retail food products.

Example 2 Twenty-two pounds or raw beef liver having a solids content ofapproximately 30% by weight was ground through a Hobart meat grinderwith Vs inch openings and charged into the autoclave of Example 1.Agitation in this case was feasible and was started prior tosteaminjection, the agitation being approximately at the same rate asabove. As agitation was commenced steam at 400 p.s.i.g. was introducedto the reaction vessel and the operation was continued for about 3%minutes at which time a terminal temperature of 390 F. was obtained.Steam-injection was stopped after 3% minutes of processing and agitationwas continued as cooling water was added to the coils and the jacket ofthe vessel. After the temperature of the product reached approximatelyF. agitation was stopped. Upon opening the autoclave approximately 25%of the material fed was collected in a fibrous shred-like form from thecoils of the agitator, the remainder being located at the bottom of thevessel in a liquid slurry. On a dry basis, the shred collected had atotal protein content of 25;% (NX6.25). The slurry had a total proteincontent of 20% on the dry basis. The product had meat-likecharacteristics offering the flavor of liver but without its non-fibroustextural quality.

Example 3 Beef hearts were transformed into a shred-like materialsimilar to that of Example 2 by the process of Example 2 except thatautoclaving was carried out for 1% minutes to a terminal temperature of360 F. The product of this process was substantially the same as that ofExample 2.

Example 4 Fish fluor produced by the solvent extraction of menhaden wastransformed into a meat-like product by employing substantially theprocess of Example 1. Nine pounds of fish flour, 5 pounds 10 ounces ofshortening and 7 pounds of Water were blended to produce a paste, 21pounds of which were charged into the autoclave of Exampie 1. Theprocess was carried out in substantially the manner of Example 1 with 1minute 30 seconds of steam injection being employed to achieve aterminal temperature of 375 F. Agitation was continued during coolinguntil a temperature of 100 F. was obtained. The process yieldedapproximately 30% of the initial solids as shred-like material similarin properties and texture to that of Example 1.

Example 5 Meat shreds were prepared from a homogeneous slurry composedof equal parts chicken paste and water using a continuous reactor. Thechicken paste was obtained from meat that was separated from the backsand necks of chicken and subsequently comminuted.

A Moyno type positive displacement pump was used to feed the slurry to aModel XID Votator. The Votator had a cylinder 3 inches in diameter and 1foot long with a shaft running the length of the cylinder which wasequipped with 2 equidistantly spaced blades extending from the shaft tothe cylinder wall. A short length of piping in which an industrialthermometer was installed to indicate product temperature connected theVotator to a water cooled double pipe heat exchanger 6 feet in length.The system extended from here to an expansion chamber 3 inches indiameter and 12 inches long which served as a holding section to collectthe product.

The entire system was first filled with water to prevent surging andflashing as it was filled with shreds and chunks. The Votator wasoperated at 30 rpm. and 550 F. Downtherm circulated through the jacketof this unit. The slurry was pumped continuously to the Votator where itwas rapidly heated from ambient to 360 F. in 1 to 2 minutes. Thematerial was cooled as it was forced through the heat exchanger and oninto the collection chamber, displacing water as it moved. Continuousoperation was maintained until the collection chamber was filled. Uponopening the holding section, meat chunks and shreds /2 to 6 inches inlength and V;

inch in diameter (pipe diameter) were collected. About 35% of the solidsby weight were collected in the form of shreds or chunks. The productwas similar to cooked chicken meat in texture and general appearance andwas considered to have a good meat texture and cohesiveness when testedin the mouth.

Example 6 Meat-like shreds were made using a soy protein isolateobtained by isoelectric point precipitation of protein solubilized fromdefatted soy meal.

Twenty pounds of soy protein isolate having a 32% solids content wasplaced into the autoclave described in Example 1. Steam was introducedthrough the steaminjection port at a pressure of 400 p.s.i.g. andcontinued for 90 seconds, ranging from 200 to 400 p.s.i.g. during thisperiod. The agitator was operated at 450 rpm. while the material washeated to a peak temperature of 360 F. after which steam injection wasterminated and cooling water circulated through the coils and jacket tolower the internal temperature to 220 F. When the autoclave was opened asolid shred-like mass was located on the coils, agitator and in theresidual liquor. The product was fibrous in appearance, quite similar tobeef chunks in texture and chewiness as well as in appearance. A 64%yield of initial solids was obtained as shreds on a weight basis.

The present composition can be described as generally comprising asinuous aggregation of comminuted, coagulated, proteinaceous tissuewhich can be unidirectionally oriented or randomly oriented. The novelcomposition of the present invention can be in the form of elasticfibers or shred-like masses. Such fibers or shredlike masses resemblethe fibers or fibrous masses of muscle tissue very closely and have manyof the desired eating qualities of meat cuts obtained from muscle tissueportions of the animal. The product can be derived from vegetable oranimal protein. The animal protein may be either beef, poultry, lamp,pork, fish, or the like, and the vegetable protein may be a proteinobtained from oleaginous nuts and seeds such as soybeans, cottonseed,peanuts, and the like.

The process of the present invention is particularly suitable inadapting certain low cost by-products of the meat packing industry suchas beef scraps and trimmings or chicken backs and necks to a morefibrous or shred-like texture of good eating quality. Similarly, theprocess of the present invention can be employed to transform theprotein of hearts, livers, kidneys, and the like such that thecomposition with respect to animal protein can be derived from ordinarystriated or cardiac muscle tissue Of particular note is the fact that inthe poultry processing industry, the utilization of chicken backs, necksand the like has always presented a problem. Heretofore, such chickenparts have been ground, debonded and sold for low cost animal feed.According to the present invention, it is now possible to process suchmaterials into high quality products which can be sold for humanconsumption thereby resulting in a much higher profit for the processor.f similar importance is the utilization of beef trimmings and scrapswhich are also used in animal feeds to prepare high quality products forhuman consumption. In addition, non-meat materials such as vegetableprotein or flour and fish flour provide eminently satisfactory meat-likeproducts when treated by the process of the present invention.

It will be understood that while the invention has been described inpart by means of specific examples, reference should be had to theappended claims for a definition of the scope of the invention.

What is claimed is:

[1. A process for preparing a meat-like protein product having ashred-like texture which comprises rapidly heating a protein material ina substantially undenatured, finely divided, hydrated state to atemperature of 300- 8 400 F., continuously agitating said proteinmaterial during heating to orient and coagulate it, and cooling saidorientated and coagulated protein material as rapidly as possible.

2. A process for preparing a meat-like protein product having ashred-like texture which comprises rapidly heating a protein material ina substantially undenatured, finely divided, hydrated state to atemperature of 300- 400 F., continuously agitating said protein materialduring heating to orient and coagulate it, and cooling said oriented andcoagulated protein material as rapidly as possible to a temperature lessthan 200 F.

3. A process for preparing a meat-like protein product having ashred-like texture which comprises heating a protein material in asubstantially undenatured, finely divided, hydrated state to atemperature of 330-360 F. in less than 5 minutes, continuously agitatingsaid protein material during heating to orient and coagulate it, andcooling said oriented and coagulated protein material as rapidly aspossible to a temperature less than 200 F.

4. A process according to claim 3 wherein the protein material has aprotein content of 30-100% of the solids on a dry basis.

5. A process for preparing a meat-like protein product having ashred-like texture which comprises finely dividing substantiallyundenatured protein material having a protein content of 30-100% ofsolids on a dry basis, adding sufiicient moisture to said proteinmaterial to form a slurry of said protein material and moisture whereinthe moisture content is 50-80%, heating said slurry to a temperature of300-400 F. in less than 5 minutes to orient and coagulate the proteinmaterial, continuously agitating said protein material during heating toorient and coagulate it, and cooling said oriented and coagulatedprotein material as rapidly as possible to a temperature less than 200F.

6. A process for preparing a meat-like protein product having ashred-like texture which comprises finely dividing substantiallyundenatured protein material having a protein content of 30-100% of thesolids on a dry basis, adding sufiicient moisture to said proteinmaterial to form a slurry of said protein material and moisture whereinthe moisture content is 50-80%, heating said slurry to a temperature of330-360 F. in less than 5 minutes to orient and coagulate the proteinmaterial, continuously agitating said protein material during heating toorient and coagulate it, and cooling said oriented and coagulatedprotein material as rapidly as possible to a temperature less than 200F.

7. The process of claim 6 wherein the heated material is rapidly cooledto a temperature of l50-100 F.

8. A process for preparing a meat-like protein product having ashred-like texture which comprises finely dividing substantiallyundenatured protein material having a protein content of 30-100% of thesolids on a dry basis, adding sufiicient moisture to said proteinmaterial to form a slurry of said protein material and moisture whereinthe moisture content is 50-80%, heating said slurry to a temperature of300-400 F. in 1-2 minutes to orient and coagulate the protein material,continuously agitating said protein material during heating to orientand coagulate it, and cooling said oriented and coagulated proteinmaterial as rapidly as possible to a temperature less than 200 F.

9. The process of claim 8 wherein the heated material is rapidly cooledto a temperature of -100 F.

10. A process for preparing a meat-like protein product having ashred-like texture which comprises finely dividing substantiallyundenatured protein material having a protein content of 30-100% of thesolids on a dry basis, adding sufiicient moisture to said proteinmaterial to form a slurry of said protein material and moisture whereinthe moisture content is 50-80%, heating said slurry to a temperature of330-360 F. in l-2 minutes to orient and coagulate the protein material,continuously agitating said protein material during heating to orientand coagulate it, and cooling said oriented and coagulated proteinmaterial as rapidly as possible to a tem perature less than 200 F.

11. The processof claim 10 wherein the heated material is rapidly cooledto a temperature of 150-100 F.

12. A product having a fibrous mass resembling high quality meat cuts intexture and appearance which comprises a sinuous aggregation ofcomminuted, coagulated, oriented proteinaceous material.

13. The product of claim 12 wherein the proteinaceous material is animalprotein.

14. The product of claim 12 wherein the proteinaceous materials is beef.

15. The product of claim 12 wherein the proteinaceous material ispoultry.

16. The product of claim 12 wherein the proteinaceous material is fish.

17. The product of claim 12 wherein the proteinaceous material is avegetable protein.

18. The product of claim 12 wherein the proteinaceous material issoybean protein] 19. A process for preparing a food product having atexture and appearance simulating that of muscle protein which comprisescharging an aqueous paste or slurry of finely divided substantiallyundenaturea' protein material to a continuous heat exchanger reactor,said protein material having a protein content of 30100% on a dry basisand a moisture content sufi'icient to establish said paste or slurry,said reactor having a reactor cylinder, a shaft running the lengththereof having blades on the shaft within the cylinder and a heat zonejacketing said cylinder and effective to rapidly heat the proteinmaterial from ambient temperature to an elevated temperature of 300- 400F. in less than 5 minutes, reacting the protein material in the reactorby heating the charge to a temperature of 300 to 400 F. in less than 5minutes while continuously agitating the paste or slurry by rotating theshaft whereby shreds are formed as the temperature of said proteinmaterial is elevated to said temperature range as said shaft rotates,withdrawing said shreds from the reactor by causing them to be forcedthrough said continuous reactor by succeeding charges of paste or slurrythereto and cooling the shreds thereafter as rapidly as possible tobelow the reaction temperature.

20. A process according to claim 19 wherein the protein material isdefatted soy flour recovered as a by-prodact of separating soy bean of}from soy beans.

21. The process of claim 20 wherein the shreds are cooled to below 200F. upon extrusion from said continuous reactor.

References Cited The following references, cited by the Examiner, are ofrecord in the patented file of this patent or the original patent.

UNITED STATES PATENTS 670,283 3/1901 Kellogg 99-17 2,165,721 7/1939Norman 992l 2,560,621 7/ 1951 Wrenshall 99-14 2,631,111 3/1953 Meyer127--69 2,682,466 6/1954 Boyer 99-14 2,830,902 4/1958 Anson et al. 99-14UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent R$L27,790Dated October 16, 1973 Invenwfls) Rusoff Irving 1.; Chan, William J.;Long, Calvin L.

It is certified that error appears in the above-identified patent andthat said Letters Patent are hereby corrected as shown below:

Claim 20, line 3 (column 10, line 16 the word 'off" should read oilSigned and sealed this 6th day of August 1971;.

(SEAL) Attest:

MCCOY M. GIBSON, JR. Attesting Officer C. MARSHALL DANN Commissioner'ofPatents

